PIV may stand for:
- Particle image velocimetry, a method to measure velocities in fluid
- Peak inverse voltage, an electronics term
- Pentium 4 microprocessor, produced by Intel ("IV" is Roman numeral for "4")
- Personal Identity Verification, as specified by FIPS 201
- Picasso-IV, an Amiga video card.
- Plena Ilustrita Vortaro de Esperanto, a dictionary of Esperanto
- Posterior interventricular artery, an artery supplying the heart
- Post indicator valve, a valve for underground fire sprinkler shutoff
- Protecting group, as Piv, Pivaloyl protecting group
- The ISO 639 language code for Vaeakau-Taumako, a Polynesian language.
- P = IV, the formula describing power in terms of current and voltage.
- Peripheral intravenous catheter or peripheral venous catheter
- Prime Instant Video, an Amazon Video streaming service